Safety, health, and environmental risk assessment of the aromatic outlet of Imam Khomeini Petrochemical Company using LOPA and fuzzy-LOPA and pollutants and control actions using the Bow-tie method.

Background: Today, with the development of the industry, the occurrence of accidents caused by the release and explosion of chemical and toxic substances in industrial units has increased, and these accidents sometimes cause irreparable damage to human life and the environment. According to a study by the American Petroleum Institute, of the recent major accidents in the last 30 years, 44% are related to machinery failure and 12% are caused by unknown factors and lack of information. Therefore, equipment risk control is aimed at preventing large and dangerous accident. The present study, the performance of LOPA and fuzzy-LOPA methods was compared toward the risk assessment of Imam Khomeini Petrochemical Company under certainty and uncertainty of data. This comparison was done in order to a conceptual method with high certainty to assess high-level hazards leading to health and safety risks and environmental pollution. Methods: First, the health, safety hazards and environmental aspects were identified via the HAZOP method. Then, a risk assessment was performed using the LOPA method. The fuzzification, severity, and likelihood of each risk were considered as an input variable and risk probability as an output variable. Finally, was the methods used in our analysis were compared and the Bow-tie software was used to draw a Bow-tie diagram to control and reduce the risks. Results: As a result, a total of 50 safety and health hazards and 37 environmental aspects were identified in the aromatic outlet of the studied company using the HAZOP method. The most critical risks identified were operational activities in feed and product tanks; flammable materials pumping; blocking the flare path; and releasing H2S gas. The results showed that the production of air pollutants in the power supply unit, disposal of waste from reactor tanks, disposal of waste from condensate tanks, and fire and explosion of the reactor are high-level environmental risks. Conclusion: In the conditions of uncertainty or the absence of information related to the probability and severity of the risk scenario, among the mentioned methods. The result showed that errors in the risk assessment were reduced to an acceptable extent by using Fuzzy LOPA method.

Risk of Pesticides Mixtures in Rice to Birds and Humans in Iran.

Rice is a staple in the diet of nearly half of the world's population. As with most crops, pesticides are used as a tool to increase crop yield in rice farming. This study investigated the residues of 14 organophosphate insecticides and 2 herbicides in rice cultivated at five locations in the southwest of Iran. The pesticide residues were then used to estimate the risk that they may pose to the health of bird and human consumers. The rice samples from the five locations contained residues from 10 to 13 pesticides. Of the 16 pesticides measured, the mean concentration of 12 pesticides exceeded the maximum residue limit set by the Iranian National Standards Organization at two or more of the sampling sites. The greatest total exceedance (sum of all pesticides detected in rice) of the species sensitivity distributions constructed for birds was 0.74% and the level of concern set for the assessment was an exceedance ≥ 5%, which suggests a relatively low risk to birds. For human consumers, no single pesticide measured in rice samples posed a considerable risk. However, when considering the mixture of pesticides present in rice samples, the cumulative risk exceeded the level of concern in all samples from all sites. The margin of safety for the mixture of pesticides present in rice samples ranged from 5.8 to 29.1, with 1 being the level of concern. The results of this study indicate that efforts need to be made to mitigate the exposure of human consumers to pesticides present in rice cultivated in Iran. This study also highlights the need to collect data on pesticides residues in other crop cultivated in Iran.

Characterization of microplastic, metals associated and ecological risk assessment in the topsoil of shiraz metropolis, south west of Iran.

This research studied the occurrence, risk assessment and metals associated with microplastic (MPs) in soil of different land-use types in the south west of Iran. One hundred samples were collected from topsoil and MPs were extracted using the floatation method. In total, 9258 MPs particles with mean of 92.85 ± 119.24 particles kg-1 were counted. The mean MPs abundance in urban soils was 2.8 and 3.2 times higher than in industrial and agricultural soils, respectively. Fragment (43%) and small MPs (100-250 µm; 41%), were the dominant shape and size, respectively. Four main polymer types including Poly Ethylene (High Density Poly Ethylene and Low Density Poly Ethylene), Nylon (PA), Poly Propylene (PP), and Poly Styrene (PS) were identified. Nylon (29%) and PE (29%) were dominant polymer types. MPs particles in soil contained different levels of metals such as Cd, Cr, Cu, Fe, Hg, Pb, Zn, and Y, except La and Yb. The mean concentrations of metals were higher in MPs than in soil. The indices of MPs-induced risk (Hstudyarea=16.8) showed a hazard level (III) in the study area. Pollution load index (PLILandusetype) showed hazard level (II) for urban soils and hazard level (I) for industrial and agriculture soils, respectively. Overall, risk index indicated high to extreme danger for MPs pollution in the study area. This is the comprehensive study on the occurrence of soil MPs and associated metals, which provides basic information for a further study concerning ecosystem health in Shiraz.

Spatiotemporal variations of 2,4-dichlorophenoxy acetic acid with the role of sugarcane industry and related human health risk assessments in the Shadegan International Wetland.

2,4-Dichlorophenoxyacetic acid (2,4-D) is the most important pesticide widely used in Khuzestan province. This study aimed to determine the ecological risks assessment in fish, plant tissues, and trends in 2,4-D urinary biomarker concentration in humans of Shadegan International wetland, Iran. Sampling was carried out from three areas: freshwater, saltwater, and brackish water. The average concentration of 2,4-D at point 38, taken from the wetland's northern parts, was 15.73 µg/L. In the lower regions, it reached 326 µg/L at point 25. From points 37 to 16, it was higher than the international standard. The increasing trend of 2,4-D concentration was observed from point 36 to the middle of the wetland. The non-carcinogenic risk through ingestion and skin contact for children and adults was 3E-3 and 1.5E-2, 2.1E-3, and 8.6E-5, respectively, and through fish, consumption was 7.1E-4 for both groups. HI values were below one (< 1), indicating no health risk. HQ values in the summer were more than one (> 1), indicating the high risk to aquatic organisms and human health.

Arsenic in drinking water and kidney cancer: a systematic review.

OBJECT: Arsenic as a chemical is found in rock, soil, air and used in various industries and their products, such as colors, hairs, and fertilizers. Humans may be exposed to arsenic mainly through food and drinking water. Due to its adverse health effects, its presence in drinking water has become a public health concern. METHODS: In this systematic review, we investigated the relationship between arsenic concentration in drinking water and the risk of kidney cancer in humans. For this reason, various electronic databases were searched from 1992 February to November 2021. In this review, three ecological studies, two case-control studies, and four cohort studies were investigated. RESULTS: High levels of arsenic (100 µg/L) have been reported in many countries such as southwest Taiwan, Niigata, Argentine, and northern Chile. A significant relationship was observed between kidney cancer incidence and its mortality rate with high arsenic levels in drinking water. CONCLUSIONS: Despite the limitations in some previous studies, reviewing and comparing the data of different regions indicates a scientific relationship between kidney cancer incidence and high concentrations of arsenic in drinking water.

Spatial distribution, source apportionment, and ecological risk assessment of elements (PTEs, REEs, and ENs) in the surface soil of shiraz city (Iran) under different land-use types.

In this study, 100 samples were collected from the topsoil of different land-use types (urban, industrial and agricultural) in Shiraz. The content of 26 elements was analyzed. CF, EF, Igeo, NPI, and PLI indices were used to evaluate soil pollution. Ecological risk assessment of metals was calculated by using Er and RI indexes. PCA analysis and the PMF model were used to determine the source of metals in soil. Also, the spatial distribution of metals and risk index were plotted using inverse distance weighting (IDW) with ArcGIS software (10.3). The metal concentrations in the soil ranged from 0.2067 ± 0.0946 (Ag) to 85,673.50 ± 4689.27 (Ca) mg kg-1. The results show that all elements' Concentration in soils was lower than the DOE level. The mean concentration of All rare earth elements (REEs) was lower than WSA and ECM values. Hotspot points pollution of some metals such as Pb, Cd, and Ni are located in high-traffic parts of the urban area. Otherwise, hot spot points of As pollution are located in industrial sample points. Results of indexes show that Sb in urban and agricultural soils have highe mean values of CF (6.75 and 6.85) and Iegeo (2.17 and 2.13), respectively. In industrial soils, S has highe mean values of CF (14.95), EF (100.26), and Igeo (2.95). The PLI index shows that REEs (PLI <1) have no pollution, but PTEs and ENs have pollution (PLI >1). The mean Er, value shows that Sb (127.33) and Cd (104) have significant risk among metals. PCA and PMF models show that The main sources of elements in shiraz soil are vehicularly emitted, fertilizer use, sewage irrigation, atmospheric deposition, and parent material. Generally, results show that Most of the study area has considerable risk, especially concerning PTEs. So, it is recommended to pay more attention to the issue of traffic in the urban environment in to improve the state of the urban area.

Measurement of polycyclic aromatic hydrocarbons in edible oils and potential health risk to consumers using Monte Carlo simulation, southwest Iran.

Persistent organic pollutants, such as polycyclic aromatic hydrocarbons, are hazardous trace contaminants frequently observed in food ingredients, such as edible oils. This study aimed to measure PAHs in forty brands of edible oils marketed in southwest Iran. Additionally, we characterized the daily intake of MOE and ILCR using Monte Carlo simulation. To analyze the content of PAHs, the liquid-liquid extraction method followed by GC-MS was utilized. The average concentration of PAHs was mostly lower than the maximum value for individual PAH (2 µg/Kg); however, the average concentration of fluorene (3.86 µg/Kg) and benzo(a)anthracene (3.13 µg/Kg) was more than the permitted level. The highest residual concentrations of PAHs were mostly observed in canola and corn oils. The daily intake of BaP and 4-PAH for 95% of consumers was 0.01 ng/kg BW/day and 0.04 ng/kg BW/day, respectively. Also, MOE was more than 10,000 for the percentiles of 5%, 50%, and 95%. The modeled ILCR showed that consumption of oil does not currently pose a cancer risk for Iranian consumers due to PAHs exposure. Concerning potential health risks, consumption of edible oils is safe; however, regular monitoring and assessment are required.

Investigation of asbestos concentration in ambient and lavage fluids of patients referred for bronchoscopy, Ahvaz.

Introduction: The amount of fibers in the lungs is considered to reflect the cumulative intensity of past asbestos exposure, and bronchoalveolar lavage (BAL) has been proposed to be a good indicator of the presence and quantity of asbestos particles in the lungs. This study evaluated the asbestos concentration in BAL fluids of asbestos-exposed and unexposed pulmonary patients and the environment of Ahvaz city. Methods: This prospective study was conducted on 80 patients underwent diagnostic fiberoptic bronchoscopy referred to Imam Khomeini Hospital in Ahvaz, Iran, in 2019. Patients with Lung diseases were divided into three groups based on CT scan results: normal (n = 32), lung cancer (n = 40) and Interstitial lung disease (n = 8). The analysis of asbestos fiber concentration in BAL fluid was carried out by Scanning Electron Microscope (SEM). Results: The positive asbestos test was detected in 69% of all subjects, including 64% of whom had asbestos-related jobs and 74.5% of those with non-related jobs (p = 0.240). The concentrations of asbestos fiber in the BAL in normal patients, lung cancer and interstitial fibrosis (ILD) were 8.13 ± 5.38, 9.66 ± 7.30 and 6.31 ± 1.98 f/ml, respectively (P = 0.492). There was no significant difference between the asbestos levels and exposure history (P = 0.877). The mean concentration of asbestos in the ambient air during the current year was 2.69 ± 0.57 f/ml (2.26-3.70), and the correlation between asbestos levels in BAL and the air was not significant (r = 0.147; P = 0.243). Conclusions: The exposure of different occupational and non-occupational groups to this carcinogenic substance indicates the need for environmental and individual control measures to reduce and prevent asbestos exposure.

Spatial distribution, ecological and health risk assessment and source identification of atrazine in Shadegan international wetland, Iran.

Recently, atrazine has been increasingly used to control weeds in the corn and sugarcane farms, which affects the water resources and aquatic organisms. In this study, atrazine residual concentrations in water and fish samples of the Shadegan wetland (Iran) were investigated. Furthermore, the health and ecological risk assessment were calculated. A total of fifty water samples were collected from the wetland during three periods with a four-month time interval. Also, ten samples of ten different fish species were analyzed at the same time. The estimation of acceptable daily intake and comparison with international standards indicates danger to adjacent residential areas of wetland. Non-carcinogenic risk analysis showed that total hazard quotient (HQing + HQderm) were below the acceptable limit and there is no danger to the residents of the area. Atrazine concentration in the water and fish samples ranged between 0 and 2175.8 µg/L, and 0 to 35.58 µg/L, respectively. Results showed that 88% of the water samples were higher than EPA and WHO guidelines for drinking water in summer. The concentrations of atrazine in fish samples in summer were more than other seasons. Analysis of ecological risk assessment also showed that considering the average atrazine concentration in three seasons, the risk exposure was very high. This study will be beneficial to the both residents and government officials in management of Shadegan wetland pollution in term of toxic compounds.

Zoning of heavy metal concentrations including Cd, Pb and As in agricultural soils of Aghili plain, Khuzestan province, Iran.

Soil is an important component of life cycle affecting agriculture and food crops. Quality of soil resources is defined according to their potential impact on human health by exposure of harmful constituents through the food chain. Heavy metals especially As, Pb and Cd are among the most hazardous elements which could be released to the top soil through different wastewaters, fertilizers, herbicides and etc. In this research Aghili plain in Khuzestan province, Iran was selected as a total of 54 samples were prepared based on a systematic gridding procedure. Selected heavy metals concentrations were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) and then zoning was performed using kriging method. Pollution level was assessed through single factor indices and pollution load index. A separate map dealing with each heavy metal was prepared to present the distribution of heavy metal in Aghili plain. In all samples the heavy metals concentrations were followed the bellow trend: Pb>As>Cd. Furthermore, based on the PLI, all stations were categorized as moderately to highly polluted sites (1

Enhanced photocatalytic degradation of tetracycline and real pharmaceutical wastewater using MWCNT/TiO2 nano-composite.

Photocatalytic degradation of tetracycline using MWCNT/TiO2nanocomposite was investigated under UVC irradiation. The effective operational parameters included pH, irradiation time, photocatalyst dosage, weight ratio of MWCNT to TiO2 and tetracycline concentration and were studied consecutively. Complete removal of tetracycline concentrations of up to 10 mg/L was obtained at MWCNT to TiO2 ratio of 1.5 (w/w%), pH 5, photocatalyst dosage of 0.2 g/L. Pseudo-first order kinetic model was best fitted with the experimental results (R2: 0.91-0.98 for different tetracycline concentrations). Based on TOC analysis, mineralization was 37% in the same reaction conditions for initial tetracycline concentration of 10 mg/L and reached to 83% after 300 min. In the case of real pharmaceutical wastewater, the COD concentration of 2267 mg/L decreased to 342 mg/L after 240 min in the same operational conditions.

Catalytic degradation of 2,4-dichlorophenoxyacetic acid (2,4-D) by nano-Fe2O3 activated peroxymonosulfate: Influential factors and mechanism determination.

2,4-Dichlorophenoxyacetic acid (2,4-D) is one of the most applicable herbicides in the world. Therefore, its residue in aquatic environment threatens the human health and ecosystems. In this study, Fe2O3 (hematite) nanoparticles (HNPs) were synthesized, and the characteristics of the obtained HNPs were determined using X-ray powder diffraction (XRD), field emission scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy (FTIR), Brunauer-Emmett-Teller (BET) technique, and particle size analyzer (PSA). The catalytic activity of HNPs was evaluated for the activation of peroxymonosulfate (PMS) for the degradation of 2,4-D. The effects of the operating parameters were studied for the PMS/HNPs system. The results showed that the acidic condition provided higher efficiency, while overdosing of PMS had a scavenging effect. The PMS/HNPs showed high efficiency in comparison with the homogeneous forms of iron (Fe2+ and Fe3+). Reusability of HNPs was studied in five consequent usages. The presence of the anions (chloride, nitrate, and hydrogen phosphate) reduced the 2,4-D degradation. Moreover, the catalytic activity of HNPs was also investigated in the presence of other oxidants. UV irradiation increased the function of PMS/HNPs and its mechanism was described. The order of 2,4-D removal for the oxidants was PMS > persulfate > H2O2 > percarbonate. A total of 29.7% of 2,4-D chlorine content was released during the destruction of 2,4-D. The quenching study showed that sulfate radical was the major agent in the degradation of 2,4-D.

Relationship between benthic macroinvertebrate bio-indices and physicochemical parameters of water: a tool for water resources managers.

The ecosystem health of rivers downstream of dams is among the issues that has become focus of attention of many researchers particularly in the recent years. This paper aims to deal with the question, how the environmental health of a river ecosystem can be addressed in water resources planning and management studies. In this study, different parameters affecting the ecosystem of river-reservoir systems, as well as various biological components of river ecosystems have been studied and among them, benthic macro-invertebrates have been selected. Among various bio-indices, biodiversity indices have been selected as the evaluation tool. The case study of this research is Aboulabbas River in Khuzestan province in Iran. The relationship between the biodiversity indices and physicochemical parameters have been studied using correlation analysis, Principal Component Analysis (PCA), and Genetic Programming (GP). Margalef index was selected as the appropriate bio-index for the studied catchment area. The relationship found in this study for the first time between the Margalef bio-index and physicochemical parameters of water in the Aboulabbas River has proved to be a useful tool for water resources managers to assess the ecosystem status when only physicochemical properties of water are known.

Removal of dichloromethane from waste gas streams using a hybrid bubble column/biofilter bioreactor.

The performance of a hybrid bubble column/biofilter (HBCB) bioreactor for the removal of dichloromethane (DCM) from waste gas streams was studied in continuous mode for several months. The HBCB bioreactor consisted of two compartments: bubble column bioreactor removing DCM from liquid phase and biofilter removing DCM from gas phase. Effect of inlet DCM concentration on the elimination capacity was examined in the DCM concentration range of 34-359 ppm with loading rates ranged from 2.2 to 22.8 g/m3.h and constant total empty bed retention time (EBRT) of 200 s. In the equal loading rates, the elimination capacity and removal efficiency of the biofilter were higher than the corresponding values of the bubble column bioreactor. The maximum elimination capacity of the HBCB bioreactor was determined to be 15.7 g/m3.h occurred in the highest loading rate of 22.8 g/m3.h with removal efficiency of 69%. The overall mineralization portion of the HBCB bioreactor was in the range of 72-79%. The mixed liquor acidic pH especially below 5.5 inhibited microbial activity and decreased the elimination capacity. Inhibitory effect of high ionic strength was initiated in the mixed liquor electrical conductivity of 12.2 mS/cm. This study indicated that the HBCB bioreactor could benefit from advantages of both bubble column and biofilter reactors and could remove DCM from waste gas streams in a better manner.

Sludge reduction by lumbriculus variegatus in Ahvas wastewater treatment plant.

Sludge production is an avoidable problem arising from the treatment of wastewater. The sludge remained after municipal wastewater treatment contains considerable amounts of various contaminants and if is not properly handled and disposed, it may produce extensive health hazards. Application of aquatic worm is an approach to decrease the amount of biological waste sludge produced in wastewater treatment plants. In the present research reduction of the amount of waste sludge from Ahvaz wastewater treatment plant was studied with the aquatic worm Lumbriculus variegatus in a reactor concept. The sludge reduction in the reactor with worm was compared to sludge reduction in a blank reactor (without worm). The effects of changes in dissolved oxygen (DO) concentration up to 3 mg/L (run 1) and up to 6 mg/L (run 2) were studied in the worm and blank reactors. No meaningful relationship was found between DO concentration and the rate of total suspended solids reduction. The average sludge reductions were obtained as 32% (run 1) and 33% (run 2) in worm reactor and 16% (run 1) and 12% (run 2) in the blank reactor. These results showed that the worm reactors may reduce the waste sludge between 2 and 2.75 times higher than in the blank conditions. The obtained results showed that the worm reactor has a high potential for use in large-scale sludge processing.